Partial discharge detecting sensor and gas insulated electric apparatus provided with a partial discharge detecting sensor

Abstract

A thin film detection electrode is formed on an insulating substrate. The resulting detection electrodes are light-weight, and have a very high dimensional accuracy so that the number of the parts supporting the detection electrodes is small and the size of the detection electrodes becomes very small. By an increase in the dimensional accuracy of the detection electrodes, reduction in insulating properties due to a water content in a insulating gas can be measured in addition to measurement of electromagnetic wave.

1 . A sensor for detecting insulation failure comprising an electrode film, formed on an insulating substrate, for detecting insulation failure, a conductor electrically connected to the electrode and a terminal, wherein the electrode film is bonded or adhered to the insulating substrate.  
   
   
       2 . The sensor for detecting insulation failure according to  claim 1 , wherein two electrode patterns are formed on the insulating substrate.  
   
   
       3 . The sensor for detecting insulation failure according to  claim 1 , wherein one of the electrode patterns is formed on one surface of the substrate and the other is formed on the other face of the substrate.  
   
   
       4 . A gas insulated electric apparatus including a metallic container filled with an insulating gas, a high voltage conductor supported by an insulator in the container, and a sensor which comprises a thin film electrode for detecting insulation failure, the thin film electrode being supported, by bonding or adhering, on an insulating substrate being self-supporting to vibration in the metallic container and having a thickness less than 5 mm, an electrode pattern formed on an insulating substrate for detecting insulation failure and a coaxial cable for transmitting electric signals to a measuring device disposed outside of the container, thereby to detect the signals.  
   
   
       5 . An insulation failure detection device comprising an electrode for detecting insulation failure, which has an electrode pattern film formed on an insulating substrate and a co-axial cable for transmitting electric signals detected by the electrode, and a measuring device for measuring the electric signals transmitted by the cable, wherein the electrode film is bonded or adhered to the insulating substrate.  
   
   
       6 . The insulation failure detection device according to  claim 5 , wherein two electrode patterns of the film are formed on the insulating substrate, one of which is connected to a core wire of the coaxial cable and the other is connected to an outer wire of the cable.  
   
   
       7 . The insulation failure detection device according to  claim 5 , wherein one of the two electrode patterns is formed on one surface of the insulating substrate and the other is formed on the other face of the insulating substrate.  
   
   
       8 . The insulation failure detection device according to  claim 7 , wherein electromagnetic wave generated upon partial discharge is detected by the electrode pattern, and a voltage induced by the electromagnetic wave is measured by the measuring device.  
   
   
       9 . The insulation failure detection device according to  claim 7 , wherein a leak current flowing between the two electrode patterns is measured to detect insulation failure.  
   
   
       10 . A gas insulated electric apparatus including a metallic container filled with an insulating gas and a high voltage conductor supported by an insulator in the container, which comprises a sensor comprising an electrode for detecting insulation failure, the electrode being supported on an insulating substrate in the container, an electrode pattern formed on an insulating substrate for detecting insulation failure and a coaxial cable for transmitting electric signals to a measuring device disposed outside of the container, thereby to detect the signals, wherein the electrode film is bonded or adhered to the insulating substrate.  
   
   
       11 . The gas insulated electric apparatus according to  claim 10 , wherein the electrode pattern for detecting insulation failure is prepared by etching a printed circuit board.  
   
   
       12 . The gas insulated electric apparatus according to  claim 10 , wherein the electrode pattern for detecting insulation failure is prepared by vacuum-evaporation of a metal film on an insulating substrate.  
   
   
       13 . The gas insulated electric apparatus according to  claim 10 , wherein the surface where the electrode pattern is formed is covered with a protecting coat.  
   
   
       14 . The gas insulated electric apparatus according to  claim 10 , wherein a pair of electrode patterns are formed on the insulating substrate, one of which is connected to a core wire of the coaxial cable and the other is connected to an outer wire of the coaxial cable.  
   
   
       15 . The gas insulated electric apparatus according to  claim 10 , wherein an electrode pattern is formed on each face of the insulating substrate, one of which is connected to a core wire of the coaxial cable and the other is connected to an outer wire of the coaxial cable.  
   
   
       16 . The gas insulated electric apparatus according to  claim 10 , wherein electromagnetic wave generated by partial discharge is received by the electrode pattern, thereby to induce a voltage upon receiving the electromagnetic wave, the induced voltage being measured by the measuring device.  
   
   
       17 . The gas insulated electric apparatus according to  claim 16 , wherein a leak current flowing between the two patterns is measured to detect the insulation failure.